Film forming method

ABSTRACT

A film-forming method comprises the steps of: (a) holding a rectangular substrate by a spin chuck provided in a cup; (b) positioning a solvent supply nozzle above the rectangular substrate and supplying a solvent to the rectangular substrate, the solvent supply nozzle having a liquid discharge port which has a length at least corresponding to that of a peripheral portion of the rectangular substrate; (c) positioning a process liquid supply nozzle above the rectangular substrate and supplying a process liquid to a portion at a rotation center portion of the rectangular substrate, thereby to form a film; (d) rotating the rectangular substrate in the cup to adjust a film thickness of the film; and (e) thereafter positioning the solvent supply nozzle above one peripheral portion of the rectangular substrate and supplying the solvent to the one peripheral portion of the rectangular substrate, whereby the film is removed from the one peripheral portion of the rectangular substrate, the substrate being subsequently rotated by the spin chuck to position the solvent supply nozzle to another peripheral portion of the rectangular substrate, whereby the film is removed from the another peripheral portion of the rectangular substrate.

BACKGROUND OF THE INVENTION

The present invention relates to a film forming method for coating aphoto-resist film or an anti-reflective coating on a layer (such as asemiconductor layer, an insulating layer, an electrode layer, or thelike) formed on a surface of a substrate or a substrate for a liquidcrystal display (LCD).

A photo-lithography technique is used in a process for manufacturing aLCD, like in a process for manufacturing a semiconductor device. In thephotolithography technique for a LCD, a resist film is formed on a glasssubstrate and is subjected to pattern exposure and further todevelopment. The semiconductor layer, the insulating layer, theelectrode layer, or the like is selectively etched to form thin filmsand electrode patterns made of ITO.

In general, a so-called spin-coating method is used in case of applyinga resist solution onto a LCD substrate. As shown in FIG. 1A, a substrateG is suctioned and maintained by a spin-chuck 701 in the spin-coatingmethod, and both of a solvent and a resist solution 9 are dropped onto arotation center portion of the substrate G. Subsequently, as shown inFIG. 1B, an upper opening is closed with a lid 713, and a rotation cup711 and a spin chuck 701 are synchronously rotated. In this manner, asshown in FIG. 2A, the resist solution 9 is diffused from the rotationcenter portion to the peripheral portion and is thereby coated over theentire upper surface of the substrate G.

When the resist solution 9 must be diffused so as to draw a circlecovering the four corner portions of the substrate as shown in FIG. 2Bif the resist solution 9 should be applied to the entire substrate G,since the substrate G has a rectangular shape. In the case of diffusingthe resist solution to the hatched regions R1 to R4 in the figure, theresist solution 9 is wasted.

However, if the supply amount of the resist solution 9 is decreased toomuch, the resist solution 9 does not sufficiently reach the cornerportions of the substrate G. Therefore, it is conventionally necessaryto supply an excessive amount of resist solution 9, and about 90% of thesupply amount of the resist solution 9 is disposed of.

In case where the resist is coated in spin-coating method, however, theresist film is thickened to rise at the peripheral edge portion of thesubstrate due to influences from the surface tension after rotationstops to stop the centrifugal force or as the time is elapsed althoughthe film thickness is uniform immediately after the film is coated.Also, in this method, an excessive portion of resist is shaken off byrotation of the substrate, and the portion of resist thus shaken off isdiffused onto the back surface of the substrate so that the resist maystick to unnecessary portions.

Thus, a non-uniform thick film formed at the peripheral portion of thesubstrate and a resist sticking to the back surface thereof causegeneration of particles in a later step of conveying the substrate, andmay further soil devices for conveying the substrate.

Therefore, after a resist is coated on the surface of the substrate,processing of removing unnecessary resists sticking to the peripheraledge portion and the back surface of the substrate. This processing isperformed after coating the resist, in a manner in which the substrateis conveyed to a resist remover unit adjacent to the resist coatingunit, a resist remover nozzle comprising a solvent supply portion and asolvent suction portion is moved along the peripheral edge of thesubstrate, a solvent for the resist is supplied, and simultaneously, theresist dissolved by supply of the solvent is suctioned and removed.

However, in case of removing a resist using the apparatus as describedabove, the resist coating unit requires an additional equipment so thatthe size of the equipment must be inevitably enlarged. In addition, thenozzle must be moved with the substrate inserted in a narrow gap betweenthe solvent supply portion and the solvent suction portion of the resistremover nozzle. Therefore, the accuracy of the positions of thesubstrate and the nozzle relative to each other must be high. Demandsfor such position accuracy become higher and higher as the size of thesubstrate has come to be enlarged in recent days.

BRIEF SUMMARY OF THE INVENTION

The present invention has an object of providing a film forming methodcapable of reducing the consumption of a process liquid where a filmhaving a uniform film thickness is formed on a substrate.

A coating film forming method comprising the steps of: (a) rotatablyholding a substrate by a spin chuck; (b) supplying a solvent for acoating film to a first portion deviated from a rotation center portionof the substrate; (c) supplying a process liquid to a second portionwhich is at the rotation center of the substrate; and (d) diffusing theprocess liquid from the second portion to a periphery thereof byrotating the substrate.

Another coating film forming method comprising the steps of: (g)rotatably holding a rectangular substrate by a spin chuck; (h) supplyinga solvent for a coating film to a first portion deviated from a rotationcenter portion of the substrate; (i) supplying a process liquid to asecond portion which is at the rotation center of the substrate; and (j)diffusing the process liquid from the second portion to a peripherythereof by rotating the substrate.

In the steps (c), it is preferable that rotation of the substrate isstopped or rotated at low speed, and the process liquid is supplied tothe second portion. In this case, the amount of scattered liquid isreduced when supplying the process liquid, and the generation amount ofmist is reduced, so that the generation amount of particles is reduced.

Since the solvent is familiar with the process liquid (i.e., the processliquid has a high solubility with respect to the solvent),,the solventdoes not repel the processing liquid but the process liquid smoothlymoves on the substrate when the process liquid supplied onto thesubstrate is brought into contact with the solvent. The solvent isthinner where the process liquid is a resist solution, for example.Otherwise, the solvent is water where the process liquid is adevelopment liquid, for example.

A coating film forming method comprising the steps of: (g) rotatablyholding a rectangular substrate by a spin chuck; (h) supplying a solventfor a coating film to a first portion deviated from a rotation centerportion of the substrate; (i) supplying a process liquid to a secondportion which is at the rotation center of the substrate; and (d)diffusing the process liquid from the second portion to a peripherythereof by rotating the substrate.

The "portion (or first portion) deviated from the rotation center of thesubstrate" indicates a region (or portion) which is deviated from thecenter point of the substrate when the substrate is rotated by the spinchuck and which is positioned between the center position of thesubstrate and the peripheral edges. In addition, the "rotation centerportion (or second portion) of the substrate" indicates a narrow region(or portion) including the center point of the substrate when thesubstrate is rotated by the spin chuck and the vicinity of the centerpoint.

The process liquid (or main liquid) supplied from the first nozzlediffuses up to the peripheral edges in the sides of the short edges of arectangular substrate from the first portion (or the portion at therotation center portion of the substrate), but is difficult to diffuse(or reach) to the peripheral edges in the sides of the long edges of therectangular substrate or to the corner portions thereof. In particular,the process liquid (or main liquid) is insufficient at the cornerportions of the rectangular substrate. However, the process liquid (orsupplementary liquid) supplied from the second nozzle diffuses (orreaches) rapidly and easily to the corner portions. This is becausethere is only a short distance from the second portion (or the portiondeviated from the rotation center portion of the substrate) to theperipheral edges of the rectangular substrate in the long edges of therectangular substrate or the corner portions thereof.

A coating film forming method comprising the steps of: (k) rotatablyholding a substrate by a spin chuck; (l) supplying a solvent for acoating film onto the substrate by a solvent supply nozzle; (m)supplying a process liquid on the substrate by a process liquid supplynozzle; (n) diffusing the process liquid by rotating the substrate; and(p) supplying the solvent to a peripheral portion of the substrate bythe solvent supply nozzle.

In so-called pre-wet processing, a solvent is supplied to a substrateprior to resist application processing in order to restrict theconsumption of the resist solution. In the present invention, the samenozzle as used in the pre-wet processing is used to remove a film fromperipheral edge portions of the substrate. Therefore, the consumption ofthe resist solution decreases, any specialized equipment is not requiredadditionally to remove a film from the peripheral edge portions of thesubstrate and position of the nozzle with respect to the substrate canbe facilitated.

Additional objects and advantages of the invention will be set forth inthe description which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. The objectsand advantages of the invention may be realized and obtained by means ofthe instrumentalities and combinations particularly pointed outhereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate presently preferred embodiments ofthe invention, and together with the general description given above andthe detailed description of the preferred embodiments given below, serveto explain the principles of the invention.

FIGS. 1A, 1B and 1C are schematic cross-sectional views for explaining aconventional film forming method;

FIGS. 2A and 2B are schematic plan views for explaining a conventionalfilm forming method;

FIG. 3 is a plan layout showing the outline of a processing system forsubjecting a LCD substrate to resist processing;

FIG. 4 is a front outer view of the LCD substrate processing system;

FIG. 5 is a plan view showing the outline of aresist-forming/peripheral-edge-resist-remover unit;

FIG. 6 is a perspective cross-sectional view showing the outline of anapparatus used in the film forming method according to an embodiment ofthe present invention;

FIG. 7 is an exploded perspective view showing a rotation cup and a lid;

FIG. 8 is a perspective block diagram showing a temperature controlcircuit for a solvent supply nozzle and a resist solution supply nozzle;

FIG. 9 is a cross-sectional block diagram showing a process solutionsupply circuit for the process solution supply nozzle and the resistsolution supply nozzle;

FIG. 10 is a flowchart showing a series of resist processing steps forthe LCD substrate;

FIG. 11 is a flowchart showing a film forming method according to anembodiment of the present invention;

FIGS. 12A, 12B, 12C, 12D, 12E, 12F, and 12G are perspective views forexplaining the outline of the film forming method according to anembodiment of the present invention, respectively showing states of theLCD substrate and the film forming apparatus in steps;

FIG. 13 is a schematic plan view showing a state where a solvent issupplied onto the LCD substrate from the solvent supply nozzle;

FIG. 14 is a schematic plan view showing a state where a resist solutionis supplied onto the LCD substrate from the resist solution supplynozzle;

FIG. 15 is a perspective view showing the outline of another resistsolution supply nozzle;

FIG. 16 is an enlarged cross-sectional view showing the outline ofanother solvent supply nozzle;

FIG. 17 is a schematic plan view showing a state where a solvent issupplied onto the LCD substrate by the another solvent supply nozzle;

FIG. 18 is a plan view showing the outline of a film forming apparatusaccording to the embodiment of the present invention;

FIG. 19 is a cross-sectional block diagram showing the outline of thefilm forming apparatus according to the embodiment of the presentinvention;

FIG. 20 is a perspective view showing a liquid supply portion of thefilm forming apparatus according to the embodiment;

FIG. 21 is a schematic plan view showing the substrate supplied with aresist solution by the film forming apparatus according to theembodiment;

FIG. 22 is a perspective view showing a peripheral edge film removersection;

FIG. 23 is a cross-sectional view showing the peripheral edge filmremover section;

FIGS. 24A, 24B, 23C, and 24D are internal schematic perspective viewsfor explaining operation of the film forming apparatus;

FIGS. 25A, 25B, and 25C are schematic plan views for explaining theoperation of the film forming apparatus;

FIG. 26 is a schematic plan view for explaining the state where a resistsolution supplied onto the substrate diffuses over the surface of thesubstrate;

FIGS. 27A, 27B, 27C, and 27D are schematic plan views showing a filmforming method according to another embodiment of the present invention;

FIG. 28 is a plan view showing a film forming apparatus according to theembodiment of the present invention;

FIG. 29 is a circuit diagram showing a film remover mechanism includedin the embodiment of the present invention;

FIG. 30 is an enlarged partial cross-sectional view showing the filmremover mechanism;

FIG. 31 is a schematic cross-sectional view showing a film formingapparatus according to further another embodiment;

FIG. 32 is a lateral cross-sectional view showing a lid having a filmremover section;

FIG. 33 is a longitudinal cross-sectional view showing an enlarged filmremover section provided at the lid;

FIG. 34 is a cross-sectional block diagram showing the outline of anapparatus used in a film forming method according to another embodimentof the present invention;

FIG. 35 is a partial cross-sectional perspective view showing a solventsupply nozzle used for coating a film;

FIG. 36 is a perspective view showing the outline of a movementmechanism for moving the solvent supply nozzle;

FIG. 37 is a side view showing a receiver member detachably attached tothe solvent supply nozzle;

FIG. 38 is a perspective view showing the outline of a movementmechanism for moving the resist solution supply nozzle;

FIG. 39 is a flowchart showing a film forming method according to theembodiment of the present invention;

FIG. 40 is a view schematically showing a state where the peripheraledge portion of a substrate is cleaned by the solvent supply nozzlehaving the receiver member in the film processing unit;

FIG. 41 is a cross-sectional view showing a modification of the solventsupply nozzle;

FIG. 42 is a perspective view showing another modification of thesolvent supply nozzle; and

FIG. 43 is a cross-sectional view showing the solvent supply nozzleformed to be integral with the resist solution supply nozzle.

DETAILED DESCRIPTION OF THE INVENTION

In the following, various embodiments of the present invention will beexplained with reference to the attached drawings.

As shown in FIGS. 3 and 4, a coating/development processing system 1comprises a loader/unloader section 2, a first process section 3, asecond process section 4, a third process section 5, and an interfacesection 6. The processing system 1 comprises various processingmechanisms for applying a photoresist solution to a LCD substrate G andfor performing development and is connected with an exposure device 7through an interface section 6.

The loader/unloader section 2 comprises a cassette mount 10 and aconveyer section 11 both extending in the X-axis direction. At most fourcassettes C1 and C2 are mounted and disposed on the cassette mount 10.LCD substrates G not yet processed are contained in two cassettes C1,and LCD substrates G already processed are contained in the other twocassettes C2. For example, each of the cassettes C1 and C2 is capable oftwenty LCD substrates G at most.

The conveyer section 11 of the loader/unloader section 2 is providedwith a first sub-arm mechanism 13. The first sub-arm mechanism 13comprises a holder for inserting and exserting substrates G into andfrom the cassettes C1 and C2, a drive mechanism for moving forwards orbackwards the holder, a X-axis drive mechanism for moving the holder inthe X-axis direction, a Z-axis movement mechanism for moving the holderin the Z-axis direction, and a θ-rotation drive mechanism for swingingand rotating the holder around the Z-axis.

The first process section 3 comprises a center conveyer path 15Aextending in the Y-axis direction, a first main arm mechanism 14Aarranged to be capable of running along the conveyer path 15A, and aplurality of processing units 16, 17, 18, and 19. Two wet cleaning units16 are provided in one side of the conveyer path 15A. The unit 16comprises a brush scrubber SCR for scrub-cleaning the surfaces of thesubstrates G with a rotation brush while applying a cleaning processingliquid to the substrates G. A heater unit 17, a dry cleaning unit 18,and a cooler unit 19 are provided at the other end of the conveyer path15A. The heater unit 17 comprises hot plates HP1 arranged in two stagesof upper and lower stages to heat the substrates G. The dry cleaningunit 18 comprises an ultraviolet cleaning device UV for cleaning thesurfaces of the substrates G by irradiating ultraviolet rays to thesubstrates G, to clean the surfaces of the substrates G.

The cooler unit 19 comprises a cooling plate COL1 for cooling thesubstrates G. The first main arm mechanism 14A comprises a holder 14afor holding the substrates G, a drive mechanism for moving forwards orbackwards the holder 14a, a Y-axis drive mechanism for moving the holder14a in the Y-axis direction, a Z-axis movement mechanism for moving theholder 14a in the Z-axis direction, and a θ-rotation drive mechanism forswinging and rotating the holder 14a around the Z-axis.

The second process section 4 comprises a center conveyer path 15Bextending in the Y-axis direction, a second main arm mechanism 14Barranged to be capable of running along the conveyer path 15B, and aplurality of processing units 21, 24, 25, and 26. Aresist-coater/peripheral-edge-resist-remover unit 21 is provided in oneside of the conveyer path 15B. The unit 21 comprises a coating device CTfor applying a resist solution while spin-rotating the substrates G, anda peripheral-edge resist remover device ER for removing a resist filmfrom the peripheral edge portions of the substrates G. Anadhesion/cooling unit 24, a heating/cooling unit 25, and aheating/heating unit 26 are provided in the other side of the conveyerpath 15B. The adhesion/cooling unit 24 comprises an adhesion device ADfor processing the surfaces of the substrates G to be hydrophobic byvapor of HMDS, and a cooling plate COL3 for cooling the substrates G.The heating/cooling unit 25 comprises a hot plate HP2 for heating thesubstrates G, and a cooling plate COL3 for cooling the substrates G. Theheating/heating unit 26 comprises hot plates HP2 arranged in two stagesof upper and lower stages, to heat the substrates G.

The third process section 5 comprises a center conveyer path 15Cextending in the Y-axis direction, a third main arm mechanism 14Carranged to be capable of running along the conveyer path 15C, and aplurality of processing units 28, 29, 30, 31, 32, 33, and 34. Threedevelopment units 28, 29, and 30 are provided in one side of theconveyer path 15C. Each of the units 28, 29, and 30 comprises adevelopment device DEV for developing and processing a resist film byapplying a development liquid to the substrates G. A titler 31, aheating/heating unit 32, and heating/cooling units 33 and 34 areprovided in the other side of the conveyer path 15C. Note that each ofthe second and third main arm mechanisms 14B and 14C has a substantiallysame structure as the first main arm mechanism 14A. In addition, acooling unit 20 is provided between the first process section 3 and thesecond process section 4, and a cooling unit 27 is provided between thesecond process section 4 and the third process section 5. The coolingunits 20 and 27 are used for temporarily keep the substrates G onstandby for processing.

The interface section 6 is provided between the third process sectionand the exposure device 7. The interface section 6 comprises aconvey/standby section 36 and a delivery section 37. The convey/standbysection 36 is provided with a second sub-arm mechanism 35 and two buffercassettes BC. The second sub-arm mechanism 35 is substantially the sameas the first sub-arm mechanism 13. Substrates G waiting for processingare contained in each of the buffer cassettes BC, and the substrates Gare temporarily kept on standby in these cassettes. The delivery section37 is provided with a delivery table (not shown), and the substrates Gare delivered between the conveyer mechanism (not shown) of the exposuredevice 7 and the second sub-arm mechanism 35.

In the next, the resist-application/peripheral-edge-resist remover unit21 will be explained below with reference to FIGS. 5 to 9.

As shown in FIG. 5, the unit 21 comprises a resist application device 22(CT) and a resist remover device 23 (ER). Two opening/closing ports (notshown) are formed in the front wall of the unit 21. A substrate G isconveyed into the resist application device 22 through one of theopening/closing ports, and a substrate G is conveyed out of theperipheral edge resist remover device 23 through the otheropening/closing port. Note that a transfer mechanism (not shown) isprovided between the resist application device 22 and the peripheraledge resist remover device 23, so that a substrate G can be transferredfrom the resist application device 22 toward the peripheral edge resistremover device 23.

As shown in FIG. 6, the resist application device 22 comprises a spinchuck 38, a rotation cup 55, a drain cup 80, and a resist solutionsupply mechanism 90. The spin chuck 38 comprises a vacuum suctionmechanism (not shown) for suctioning and holding a substrate G, and arotation drive mechanism 42 for rotating a substrate G. The rotation cup55 is provided so as to surround the periphery of the spin chuck 38.Further, the drain cup 80 is provided so as to surround the periphery ofthe rotation cup 55. A lid 71 is arranged to be covered over an upperopening of the rotation cup 55. A plurality of drain tubes 80d areequipped on the bottom portion of the drain cup 80, and mist and a wasteliquid are drained through the drain tubes 80d to a collection/recycledevice (not shown). A processing liquid supply mechanism 90 comprises asolvent supply nozzle 91, a resist supply nozzle 92, a motor 105, and aswing arm 106.

The peripheral edge resist remover device 23 comprises four solventdischarge nozzles 23a and a scanning movement mechanism 23b for movingthe nozzles 23a so as to scan a substrate G along the edges thereof, anda mount 23c for suctioning and holding the substrate G.

In the next, the resist application device 22 will be explained morespecifically with reference to FIGS. 6 to 9.

A rotation shaft 43 is connected to a lower portion of the spin chuck38. The rotation shaft 43 is connected with an elevation cylinder 42through a vacuum seal portion 40 and is slidably supported on a lowerportion of the rotation cup 55 through a sprite bearing 44.

Further, the sprite bearing 44 is equipped with a slave pulley 50a, anda belt 52a is bridged between the slave pulley 50a and a drive pulley51b. The drive pulley 51b is installed on a drive shaft 51a of a motor51. In addition, the spin chuck 38 is supported so as to elevate freelyby an elevation cylinder 42.

The rotation cup 55 is provided so as to surround an upper portion andan outer peripheral portion of the spin chuck 38. A processing chamber56 for processing a substrate G is formed inside the rotation cup 55,and an opening portion 55c is formed at the center of the lower surface55b of the rotation cup 55. The spin chuck 38 is inserted into theprocessing chamber 56 from the opening portion 55c.

At the lower portion of the rotation cup 55, the lower surface 55b ofthe rotation cup 55 is connected to an upper end portion of the rotationouter cylinder 61b through a connection cylinder 60, and the rotationouter cylinder 61b is connected to a fixed collar 63 through a bearing62b. The fixed collar 63 is connected to the rotation inner cylinder 65athrough a bearing 64, and a rotation shaft 43 is connected to therotation inner cylinder 65a through a spline bearing 44. Further,labyrinth seals (not shown) are respectively formed on surfaces of thefixed collar 63 and the rotation inner cylinder 65a opposed to eachother and surfaces of the fixed color 63 and the rotation outer cylinder61b opposed to each other. Particles generated by lower drive mechanisms42, 44, 51, 51a to 52a, 62b, and 64 are prevented from entering into aprocessing space 56 by the labyrinth seals.

The rotation outer cylinder 61b is equipped with a slave pulley 66b. Arotation drive force is transferred to the slave pulley 66b from a drivepulley 51b of a motor 51 through a belt 67b from the slave pulley 66b.Meanwhile, the diameter of the slave pulley 50a is equal to the diameterof the slave pulley 66b, and both of these pulleys are driven androtated by a common motor 51, so that the spin chuck 32 and the rotationcup 55 are rotated in synchronization with each other.

As shown in FIG. 7, a plurality of fixing pins 71a are projected upwardsfrom the upper surface 55d of the rotation cup surrounding the upperopening 55c. The fixing pins 71a are arranged to be engaged respectivelywith concave portions 71b of the lid 71, and the lid 71 is engaged withthe rotation cup 55 by respectively engaging the concave portions 71bwith the fixing pins 71a. In addition, each of the top portions of thefixing pins 71a is formed like a spherical surface so that dust isprevented from being generated by contacts between the top portions andthe concave portions 71b.

As shown in FIGS. 6 and 7, a plurality of air supply ports 72 arepenetrated through the vicinity of the center of the lid 71. Inaddition, a support portion 73 extends from the center of the lid 71. Aplurality of stopper grooves 74 are formed in an end 74 of the supportportion 73. The stopper grooves 74 are engaged with engaging pins (notshown) projected from a robot arm 75, and the lid 71 is detached fromthe rotation cup 55 by these components.

The side wall of the rotation cup 55 is formed such that the inner sidesurface thereof is in a tapered shape whose diameter decreases upwards.Therefore, when an air is supplied from an air supply port 72 of the lid71, the air flows along the upper surface of a substrate G and furtheralong the tapered surface. The air is drained to the drain cup 80through a lower exhaust port 76 of the rotation cup 55.

The drain cup 80 is provided so as to surround the rotation cup 55. Thedrain cup 80 is formed like a hollow ring-like shape. The drain cup 80receives a waste liquid and waste mist drained from the rotation cup 55,and exhausts the liquid and mist to a drain unit (not shown) and anexhaust unit (not shown) or a recycle unit (not shown). A circular path80a is provided inside the drain cup 80. The circular path 80a isdivided like a detour (or crank) by a wall 80b standing on the bottomportion of the drain cup 80 and a wall 80c hanging from a ceilingportion of the drain cup 80. A plurality of drain ports 80d are formedin the bottom portion positioned between the walls 80b and 80c.

For example, four exhaust ports 81 are formed in the outercircumferential wall of the circular path 80a, and each of the exhaustports 81 communicates with the suction side of the exhaust unit (notshown). Mist of a resist solution generated in the processing chamber 56flows to the drain cup 80 through the exhaust port 76, and is furtherexhausted to the outside through the exhaust ports 81 through thecircular path 80a.

As shown in FIGS. 8 and 9, the processing liquid supply mechanism 90comprises a solvent supply nozzle 91 for discharging and supplying asolvent 9, a resist solution supply nozzle 92 for discharging andsupplying a photoresist solution 9. The nozzles 91 and 92 are installedand supported on the top end portion of a common horizontal arm 106. Thebase end portion of the horizontal arm 106 is connected to and supportedon a swing mechanism 105. The swing mechanism 105 comprises a steppingmotor (not shown). By the stepping motor, the horizontal arm 106 isswung around the Z-axis by the stepping motor, and the nozzles 91 and 92are moved between a home position and a use position, as shown in

As shown in FIG. 9, the solvent supply nozzle 91 communicates with thetank 97 through the tube 95. The tube 95 is provided with anopening/closing valve 96 controlled to be turned on/off by a controller48. A solvent 8 is contained in the tank 97, and a pressure gas supplysource (not shown) communicates with the tank 97 through a supply tube98. Operation of the pressure gas supply source is controlled by thecontroller 48, and the supply amount of the solvent 8 conveyed to thenozzle 91 is adjusted by controlling a gas pressure by the controller48. The solvent 8 will be, for example,propyleneglycolmonomethyletheracetate (PGMEA), an ethyllactate (EL),ethyl-3-ethoxypropione (EEP), or the like.

The resist solution supply nozzle 92 is constructed in a substantiallysame structure as the solvent supply nozzle 91. The resist solutionsupply nozzle 92 communicates with the tank 101 through a tube 99. Thetube 99 is provided with an opening/closing valve 100 controlled to beturned on/off by the controller 48. A photoresist solution 9 iscontained in the tank 101, and a pressure gas supply source (not shown)communicates with the tank 101 through a supply tube 102. Operation ofthe pressure gas supply source is controlled by the controller 48, andthe supply amount of the photoresist solution 9 fed to the nozzle 92 isadjusted by controlling the gas pressure by the controller 48. Thephotoresist solution 9 may be, for example, a solution in which amixture of a quinonediazide-based photosensitive agent and phenol-basedresin (which is alkaline-soluble) is dissolved in an appropriate amountof solvent 8.

Further, the temperatures of the solvent 8 flowing through the tube 95and the resist solution flowing through the tube 99 are respectivelycontrolled to target temperatures by a temperature control mechanism110. That is, as shown in FIG. 9, jackets 111 are provided so as tosurround the outsides of the jackets 111, respectively. A heat exchangemedium 12 is circulated in each jacket 111 through a circulation circuit112. A pump 113 and a thermo module 114 are provided in this order onthe circulation circuit 112. Operation of the pump 113 and the thermomodule 114 is controlled by the controller 48. The thermo module 114serves to maintain the heat exchange medium 12 at a constant settemperature. Note that the tubes 95 and 99 are respectively surroundedby the jackets 111 nearly to the vicinity of the top end portions. Inthis manner, the temperatures of the solvent 8 and the resist solution 9are controlled to target temperatures (e.g., 23° C.).

Next, a series of resist processing of a LCD substrate will be explainedwith reference to FIGS. 10 to 14. In particular, detailed explanationwill be made of a case of applying a resist to a substrate G.

One piece of substrate G is picked up from a cassette C1 by the firstsub-arm mechanism 13 (in a step S1). The substrate G is delivered to thefirst main arm mechanism 14A from the first sub-arm mechanism 13. Thefirst main arm mechanism 14A conveys the substrate G to the first mainarm mechanism 14A from the first sub-arm mechanism 13. In the cleaningunit 18, ultraviolet rays are irradiated to the substrate G in thepresence of ozone to subject the surface of the substrate G to UV-ozonecleaning (in a step S2). Further, the substrate G is conveyed to thecleaning unit 16 by the first main arm mechanism 14A, and the surface ofthe substrate G is subjected to scrub-cleaning while applying a cleaningliquid to the substrate G (in a step S3). Subsequently, the substrate Gis rinsed with pure water and is then dried (in a step S4).

Next, the first main arm mechanism 14A delivers the substrate G to thesecond main arm mechanism 14B by the unit 20. The second main armmechanism 14B conveys the substrate G to the adhesion unit 24. In theadhesion unit 24, HMDS vapor is made act while heating the substrate G,thereby to make the surface of the substrate hydrophobic (in a step S5).Further, the substrate G is cooled to a target temperature by a coolingsection COL3 by temperature control. The substrate G is conveyed to theunit 21 and a resist solution is coated to the substrate G (in a stepS6). Subsequently, a resist film 9b is removed from the peripheral edgeportion of the substrate G (in a step S7). Note that the inside of theunit 21 is kept exhausted during the steps S6 and S7.

The resist coating step S6 will be explained more specifically withreference to FIG. 11. When the second main arm mechanism 14B reaches theunit 21, a shutter (not shown) is opened and the lid 71 is detached fromthe cup 55 by the robot arm 75. The second main arm mechanism 14B movesforward the holder 14b and conveys the substrate G into the resistcoating section 22 of the unit 21 (in a step S611). The spin chuck 38 iselevated up and the substrate G is moved onto the spin chuck 38 from theholder 14b, and the substrate G is vacuum suctioned and maintained bythe spin chuck 38 as shown in FIG. 12A (in a step S612). The holder 14bis moved back from the unit 21 and the shutter is closed.

The swing mechanism 105 swings the horizontal arm 106 and moves both thenozzles 91 and 92 to use positions from home positions. In this manner,the resist solution supply nozzle 92 is positioned just above therotation center portion (or second portion) of the substrate G, and thesolvent supply nozzle 91 is positioned just above the intermediateportion (or first portion) of the substrate G (in a step S613). The"rotation center portion (or second portion) of the substrate G"indicates a narrow region including the center point of the substrate Gand the vicinity of the center point when the substrate G is rotated bythe spin chuck 38. The "intermediate portion (or first portion) of thesubstrate G" indicates such a region which is deviated from the centerpoint of the substrate G and is positioned in the middle between thecenter point of the substrate G and the peripheral edge thereof.

The temperature of thinner 8 in the flow path of the solvent supplynozzle 91 is controlled to a target temperature of 23° C.±1° C. Thetemperature of the resist solution 9 in the flow path of the resistsolution supply nozzle 92 is controlled to the same target temperatureas above.

The motor 51 is started to start synchronous rotation of the substrate Gand the cup 55 (in a step S614). While the substrate G is rotated at afirst rotation speed of 200 rpm, the solvent 8 is supplied toward afirst portion of the substrate G only for about two seconds, and then, acircular solvent application region 8a is formed as shown in FIG. 12B.Further, the solvent application region 8a spreads to the periphery (ina step S615).

As shown in FIG. 13, the solvent 8 is supplied to a point P deviatedfrom the rotation center point Q of the substrate G. For example, thesupply point P is preferably the position which is located on an innerside to the outer peripheral edge portion of the spin chuck 38 in theplan view of FIG. 13. In the case where the point P is located on anouter side to the outer peripheral edge portion of the spin chuck 38,the solvent 8 collides with the edge portion of the substrate being inrotation, thus causing the scattering of the solvent. Conversely, in thecase where the point P is located on an inner side to the outerperipheral edge portion of the spin chuck 38, the scattering of thesolvent will not occur. Once the solvent 8 is supplied to the point P,the solvent 8 diffuses toward the outside of a circle having a radius PQaround the point Q situated as its center, and a solvent applicationregion 8a hatched with oblique lines in FIG. 13 is formed. As a resultof this, a non-application region 39 applied with no solvent 8 is formedat the center of the substrate G.

Supply of the solvent 8 from the nozzle 91 to the substrate G is stopped(in a step S616). Subsequently, the substrate G is rotated at a rotationspeed of 200 to 800 rpm for three to five seconds to reduce the amountof solvent 8 existing on the substrate G (in a step S617). In the stepS617, the rotation speed of the substrate G is preferably 600 rpm, forexample, and the substrate G is rotated preferably for about threeseconds at the rotation speed.

The drive of the motor 51 is stopped so that the synchronous rotation ofthe spin chuck 38 and the cup 55 is stopped, thereby to make thesubstrate G stand still (in a step S618).

Next, supply of a resist solution 9 is started to the non-applicationregion 39 (e.g., the rotation center portion of the substrate G; thesecond portion) from the nozzle 92 (in a step S619). As shown in FIGS.12D and 14, the resist solution 9 is supplied to the rotation centerpoint Q of the substrate G. In this time, the supply amount of theresist solution 9 is 14 cc and the supply period of the resist solution9 is about three seconds. After supply of the resist solution 9 to thesubstrate G is completed (in a step S620), the nozzles 91 and 92 aremoved back to home positions from use positions by the swing mechanism105.

As shown in FIG. 12E, the lid 71 is covered over the cup 55 by the robotarm 75 and the upper opening 55c is closed by the lid 71, so that theperipheral atmosphere is of the substrate G is kept air-tight (in a stepS621). Subsequently, as shown in FIG. 12F, the spin chuck 38 and therotation cup 55 are rotated in synchronization with each other at asecond rotation speed higher than the first rotation speed describedbefore (in a step S622). In this manner, the resist solution 9 suppliedonto the substrate G is diffused and the film thickness of the resistfilm 9a to be formed on the substrate G is adjusted. Note that thesecond rotation speed in the step S622 is preferably 600 to 800 rpm.Mist generated in the processing chamber 56 when rotating the substrateG flows into the drain cup 80 and is exhausted to the outside throughthe exhaust port 81. Therefore, mist is prevented from rising up andpolluting the upper side of the rotation cup 55.

Rotation of the substrate G is stopped (in a step S623). By this seriesof steps S611 to S623, a resist film 9a aimed as a target is formed onthe upper surface of the substrate G (in a step S6). As shown in FIG.12G, the lid 71 is detached from the cup 55 by the robot arm 75 (in astep S624). The substrate G suctioned and held by the spin chuck 38 isreleased. The substrate G is grasped by a chuck portion of a conveymechanism (not shown), and is conveyed out of the resist coating section22 to the peripheral edge resist remover section 23 (in a step S625).

In the peripheral edge resist remover section 23, the mount table iselevated up and the substrate G is transferred onto the mount tableafter the substrate G is conveyed into the section. The mount table iselevated down and the substrate G is positioned with respect to fournozzles 23a. Subsequently, the solvent 8 is discharged from the nozzles23a while moving the nozzles 23a along the four edges of the substrateG, respectively. The resist film 9b is dissolved and removed from theperipheral edge portion of the substrate G (in a step S7).

Next, the second main arm mechanism 14B conveys the substrate G out ofthe unit 21 to the unit 26. The resist film 9a is subjected topre-baking processing (in a step S8). Further, the substrate G is cooledin the cooling unit 27 and the substrate G is conveyed into the exposuredevice 7 through the interface section 6. The resist film 9a issubjected to pattern exposure by the exposure device 7 (in a step S9).Subsequently, the substrate G is conveyed to the development unit 30 andis subjected to development processing by applying a developmentsolution to the resist film 9a (in a step S10). Further, the substrate Gis rinsed with pure water (in a step S11) and is then dried (in a stepS12). Further, the substrate thus processed is sequentially conveyed bythe main arm mechanisms 14A, 14B, and 14C and is then contained into acassette C2 of the loader/unloader section 2 by the first sub-conveyerarm 13 (in a step S13). Finally, substrates G together with the cassetteC2 are conveyed out of the system 1 to a processing device of a nextstep.

According to the embodiment described above, when supplying the resistsolution 9 to a substrate G, the substrate G stands still (or stopsrotating) and the resist solution 9 is therefore prevented fromscattering to the periphery, so that the generation amount of particlesis extremely small.

In addition, since the resist solution 9 is supplied after supplying asolvent 8 to the substrate G, the resist solution 9 reaches to thecorner portions of the periphery of the substrate G. Accordingly, auniform resist film can be formed on the substrate G. Further, since thecoating solution is not brought into contact with the solvent and isdiffused while it is not diluted, a coating film can be made to havemore uniform thickness. Further, since the resist solution 9 is suppliedafter the solvent 8 on the substrate G is spreaded and reduced, theamount of scattered resist solution can be reduced without reducing theadhesion between the resist solution 9 and the substrate G is notreduced more than in the case where the solvent 8 is not reduced.

Further, since scattering of the resist solution 9 is reduced, theresist solution 9 supplied onto the substrate G more efficientlycontributes to formation of a resist film than in a conventional case,and therefore, the amount of resist solution 9 required for resistapplication processing can be saved.

In addition, the solvent 8 is supplied to a point P derived from therotation center portion of the substrate G, and the center of thesubstrate G is not supplied with the solvent 8 (ref. FIGS. 13 and 14).

Therefore, the consumption amount of the solvent 8 can be reduced by anamount saved by not supplying the solvent 8 to the rotation centerportion of the substrate G.

After a resist film having a predetermined thickness is thus formed on asubstrate G, rotation of the spin chuck 32 and the rotation cup 55 isstopped together, and the lid 71 closing the opening portion 55a of therotation cup 55 is released. In this time, in the processing chamber 56of the rotation cup 55, air introduced from the air supply ports 72 isexhausted from the exhaust port 76, so that the pressure inside theprocessing chamber 56 is not decreased under a necessary negativepressure. Therefore, a large force is not necessary to release the lid71. Therefore, the lid 71 can be released with ease.

The supply timings and the supply spots at which the solvent 8 and theresist solution 9 are supplied for a substrate G are not limited tothose as described in the above embodiment. For example, the solvent 8and the resist solution 9 may be simultaneously supplied to a substrateG. The processing time can be much more shortened by simultaneous supplyof the solvent 8 and the resist solution 9, so that the throughput canbe improved. Also, for example, the solvent 8 may be supplied to anotherspot than the point P. By supplying the solvent 8 to a plurality ofspots, the solvent 8 can be thoroughly diffused to the corners of thesubstrate G. Therefore, the amount of the solvent consumed can bereduced.

In addition, after simultaneously supplying the solvent and the resistsolution 9 to the substrate G, the substrate G is rotated. Therefore,the resist solution 9 can be uniformly diffused to the corner portionsof the substrate G, so that the resist film has a uniform thickness.

Further, since the solvent 8 and the resist solution 9 are supplied to asubstrate G which stands still, the amounts of solvent 8 and resistsolution 9 scattered to the outside can be restricted. In addition,since the substrate G is rotated after the lid 71 is covered over thecup 55 to make an air-tight processing atmosphere, the resist solution 9on the substrate G are not scattered to the outside or periphery of thecup 55, so that the periphery is prevented from being polluted.

In the above embodiment, it has been explained that the solvent 8 issupplied to a point P corresponding to the vicinity of the outerperiphery of the spin chuck 38. However, the present invention is notlimited to the embodiment. Specifically, if the rotation speed and therotation period of the LCD substrate are changed in the step of reducingthe solvent 8, the solvent 8 can be supplied to a position outside thepoint P. In this case, if the solvent 8 is supplied to a position insidethe inscribed circle of the substrate G, it is possible to restrict lossof the solvent 8 supplied to the substrate G.

In addition, a linear type nozzle 115 shown in FIG. 15 can be used inplace of the resist solution supply nozzle 92 described above.

Although the above embodiment has been explained to a case of supplyingthe solvent 8 to the first portion of a substrate G from the supplynozzle 91, the present invention is not limited hitherto, but thesolvent can be supplied to the substrate G using a different type ofsupply nozzle 116 as shown in FIG. 16. The liquid discharge port 119 ofthis type of supply nozzle 116 forms a circular slit. When a solvent 8supplied through an opening 117, is discharged from the liquid dischargeport 119 toward a substrate G, as shown in FIG. 17, a circular solventapplication region 8a (which is the hatched portion in the figure) isformed on the substrate G around a center of the point Q. Further, anozzle 120 may be provided at the center of the lower surface of thenozzle 116 and a resist solution 9 is supplied to a flow path 122 fromresist supply sources through a supply port 121 so that the resistsolution 9 is discharged from the nozzle discharge port 123 to therotation center point Q of the substrate G. In this case, it is possibleto supply the solvent 8 and the resist solution 9 to the substrate Gsubstantially at the same time, so that the throughput of processing canbe improved much more. Alternatively, it is possible that the substrateis rotated at such a rotation speed that the coating solution would notscatter. With this manner, the distribution of the process liquid afterthe supply of the process liquid becomes even more uniform, thusimproving the uniformity of the thickness of the film.

In addition, the rotation speed of the spin chuck 38 and the rotationspeed of the rotation cup 55 may be changed by changing the sizes of theslave pulley 50a and the slave pulley 66b. Further, the presentinvention is not limited to LCD substrates but is applicable to a caseof processing a semiconductor wafer having a large diameter.

According to the present invention, after a solvent is applied, aprocess liquid diffuses over the solvent. Therefore, the process liquidcan be diffused over to the peripheral portion of a substrate andparticularly to the corner portions thereof. As a result, it is possibleto obtain a film having a uniform thickness. The technique of removingthe solvent is not limited to the swinging out by the rotation of thesubstrate, but the same effect can be achieved by some other techniquesincluding the drying by heat.

In addition, when supplying the process liquid onto the substrate,rotation of the substrate is stopped. It is therefore possible torestrict scattering of the process liquid. As a result, pollution of theoutside of the substrate can be prevented. In addition, since a solventis supplied to a portion deviated from the rotation center portion ofthe substrate, the solvent content in the process liquid can be reducedmore than in a conventional apparatus.

Further, the coating solution is diffused while it is not diluted, andtherefore a coating film having more uniform thickness can be obtained.

Further, since the process liquid is supplied after the solvent suppliedonto a substrate is reduced, the scattering amount of the process liquidis reduced so that the yield of the process liquid is increased.

In addition, the process liquid is supplied to a substrate kept standingstill, and the lid is closed when rotating the substrate to diffuse theprocess liquid. Therefore, the process liquid is prevented fromscattering to and polluting the outside of the processing apparatus. Asa result, decrease of the yield can be restricted.

Further, since the process liquid and the solvent thereof aresimultaneously supplied to a substrate, the throughput can be improvedmuch more than in the case where the process liquid and the solventthereof are separately supplied to the substrate.

Next, a second embodiment of the present invention will be explainedbelow with reference to FIGS. 18 to 33.

The resist coating mechanism 22A of the second embodiment has a nozzleassembly 205 comprising five solvent supply nozzles 251a, 251b, 251c,251d, and 251e, and one resist supply nozzle 252. This kind of nozzleassembly 205 is capable of simultaneously supplying the solvent 8 to thefour corners and the center of a substrate G.

A spin chuck 38 is provided in the substantial center of the resistcoating mechanism 22A. An upper portion of the spin chuck 38 is formedin a disk-like shape and has a diameter smaller than shorter edges ofthe substrate G. The spin chuck 38 is substantially the same as that ofthe first embodiment, and comprises a vacuum suction mechanism, arotation drive mechanism, and an elevation mechanism.

The rotation cup 55A is provided so as to surround the spin chuck 38.The rotation cup 55A has an opened cylindrical shape having a bottom andan upper opening 55c, and the opening 55c is covered with a lid 231. Thelid 231 can be detached from the by a robot arm 242.

A rectification plate 232 is provided in the rotation cup 55A. Therectification plate 232 is connected with the lid 231 by a support shaft243, faces the spin chuck 38, and is larger than the substrate G. AnO-ring 39 is provided between the bottom surface of the rotation cup 55Aand the lower surface of the spin chuck 38. When the spin chuck 38elevates down, the lower surface of the spin chuck 38 is brought intocontact with the O-ring 39, and the inside of the rotation cup 55A iskept air-tight.

A drain cup 80A is provided so as to surround the rotation cup 55A. Thedrain cup 80A is covered with a lid 241. The lid 241 is connected withthe lid 231 through a support shaft 243. Specifically, the two lids 231and 241 and the rectification plate 232 are formed to be integral witheach other and can be detached together from the cups 55A and 80A.

Air holes 234a and 244a are respectively formed in the vicinities of thecenters of the lids 231 and 241. An exhaust port 234b is formed in theperipheral edge side of the bottom surface of the rotation cup 55A. Aplurality of drain ports 245a are provided in the peripheral edge sideof the bottom surface of the drain cup 80A, and an exhaust port isformed inside the drain ports 245a.

The spin chuck 38 is connected to a motor drive shaft 51a through beltmechanisms 50a, 52a, and 51b. In addition, the spin chuck 38 issupported by an elevation cylinder 42 through a shaft 43 such that thespin chuck 38 can be elevated up and down. The elevation cylinder 42 hassuch an elevation stroke extending that extends from a processingposition of the substrate G where the upper surface of the spin chuck 38is positioned in the rotation cup 55A to a transfer position of thesubstrate G where the upper surface of the spin chuck 38 is positionedabove the upper end of the drain cup 80A. In addition, the suction hole(not shown) of the spin chuck 38 communicates with a vacuum suctiondevice not shown through a hollow rotation shaft 43 and a vacuum sealportion 40.

The rotation cup 55A is equipped at the top portion of the rotationcylinder 61b by a connection cylinder 60, and the outer circumferencesof the rotation cylinder 61b and the connection cylinder 60 are equippedwith slave pulleys 50a and 66b having an equal diameter. Belts 52 and 67are respectively wound to be bridged between the drive pulley 51b andthe slave pulleys 50a and between the drive pulley 51b and the slavepulley 66a. The spin chuck 38 and the rotation cup 55A are rotated insynchronism with each other by driving of a common motor 51.

A nozzle assembly 205 is provided at an end portion of the resistapplication mechanism 22A. As shown in FIG. 20, the nozzle assembly 205comprises a rectangular block 250 for supporting five nozzles 251a,251b, 251c, 251d, and 251e, and a nozzle 252 for supplying a solvent 8.The rectangular block 250 is equipped on the top end of a movable arm253, and the movable arm 253 is supported such that the arm 253 can beswung around the Z-axis by a swing mechanism 254.

Next, supply of a liquid (e.g., a solvent or a resist solution) from thenozzles 251a, 251b, 251c, 251e, and 252 will be explained with referenceto FIGS. 20 and 21.

The first nozzle 251a and the sixth nozzle 252 are arranged and disposedin the substantial center of the rectangular block 250. A resistsolution 9 is supplied from the first nozzle 251a to a portion Ra in therotation center portion of the substrate G. A solvent 8 is supplied fromthe sixth nozzle 252 to a portion Ra of the rotation center portion ofthe substrate G. The solvent 8 supplied from the sixth nozzle 252 is aso-called pre-wet liquid for previously moistening the substrate Gbefore supplying the resist solution 9. The second, third, fourth, andfifth nozzles 251b, 251c, 251d, and 251e are respectively provided tofour corners of the rectangular block 250. As shown in FIG. 21, resistsolutions 9 are respectively supplied from the nozzles 251b, 251c, 251d,and 251e to portions Rb, Rc, Rd, and Re of four corner regions thesubstrate G (which are portions where the supply amount of the resistsolution 9 diffused from the portion Ra at the rotation center portionis insufficient). The portions Rb, Rc, Rd, and Re are positioned outsidea concentric circle 88 indicated by a two-dot chain line in FIG. 21, atpositions slightly deviated in the rotation direction of the substrate G(e.g., in the clockwise direction indicated by an arrow in the figure)from the diagonal lines L1 and L2 indicated by one-dot chain line in thefigure. Note that the concentric circle 88 indicates a range which theresist solution 9 diffused from the portion Ra at the rotate centerportion can reach. It is important that the diameter of the concentriccircle 88 is slightly larger than the length of the short edges of thesubstrate G.

If a resist solution 9 is supplied to the portions Rb, Rc, Rd, and Re,the resist solution 9 is diffused from the portions Rb, Rc, Rd, and Reas shown in FIG. 26 when the substrate G is rotated, and the resistsolution 9 is charged to each of the four corner regions of thesubstrate G. As a result, the resist solution 9 thoroughly spreads overthe entire surface of the substrate G, and a resist film 9a having auniform film thickness is formed.

As shown in FIGS. 19 and 20, the first to fifth nozzles 251a, 251b,251c, 251d, and 251e communicate with a resist solution tank 256 throughsupply tubes 255a to 255e, respectively. Each of the supply tubes 255ato 255e is provided with a suck-back valve V1, an air operation valveV2, a scrub remover mechanism 257, a filter 211, and a bellows pump 258.

The bellows pump 258 can be expanded and driven by a drive section 259.A controller 248 controls the drive period and the drive speed of thebellows pump 258 and opening/closing operation of the air operationvalve V2, thereby to adjust the supply amount of the resist solution 9from the nozzles 251a to 251e. In place of using the bellows pump 258, apressure gas of N₂ may be introduced into the tank 256 thereby to conveythe resist solution 9. In this case, the controller 248 adjust thesupply amount of the resist solution 9 by controlling the pressure ofthe N₂ gas.

The sixth nozzle 252 communicates with a solvent tank 252c through thesupply tube 252a and the opening/closing valve 252b. The controller 248adjust the supply amount of the resist solution 9 by controlling thepressure of the pressure gas of N₂ introduced into the solvent tank252c.

Further, a peripheral edge film remover section 23A is provided outsidethe drain cup 80A. The peripheral edge film remover section 23Acomprises an edge remover 260 as shown in FIGS. 22 and 23. Arms 261a and261b are equipped at both ends of the edge remover 260. The arm 261a ismoved in the horizontal direction by the drive mechanism 262, therebymoving the arm 261b in the horizontal direction along a guide rail 263.Thus, the edge remover 260 comes close to or apart from the outerperipheral edges of the substrate G.

The edge remover 260 has a length slightly larger than the long edges ofthe substrate G, and end plates 264a and 264b are equipped at both endsof the edge remover 260. A slit-like solvent discharge portion 266 isprovided on the upper surface of the edge remover 5 260, and the solvent8 is sprayed to the portion slightly deviated inwards from the end edgesof the upper surface of the substrate G, by the discharge portion 266.

A header 265 made of quartz is provided at an upper portion of the edgeremover 260. The header 265 communicates with the solvent tank 252cthrough a flexible tube 252d, and the inside of the tank 252c is filledwith the solvent 8. Further, a slit 265a is formed in the bottom surfaceof the header 265 so as to correspond to the solvent discharge portion266.

A slit-like solvent discharge portion 267 is provide at the lowersurface side of the edge remover 260 and sprays the solvent 8 toportions in the vicinity of the end edges of the substrate G, thereby toremove an unnecessary resist film 9b. A plurality of suction tubes 268forming suction/exhaust paths are connected, at intervals, to the sidesurface of the edge remover 260. Dissolved materials of the resist andan excessive solvent are suctioned and exhausted through a suction pumpnot shown.

In the next, operation of the above apparatus will be explained withreference to FIGS. 24A to 24D and FIGS. 25A to 25C.

As shown in FIG. 24A, with the lids 231 and 241 detached form the cups55A and 80A, the spin chuck 38 is elevated up, and the substrate G istransferred to the spin chuck 38 from the holder 14b of the main armmechanism and is suctioned and held thereon.

As shown in FIG. 24B, the spin chuck 38 is elevated down and a solvent 8is supplied from the sixth nozzle 252 to the portion Ra at the rotationcenter portion of the substrate G. For example, a mixture of PGME andPGMEA is used as the solvent 8. Subsequently, a resist solution 9 issupplied from the first nozzle 251a to the portion Ra at the rotationcenter portion of the substrate G. Further, resist solutions 9 aresupplied from the second to fifth nozzles 251b to 251e to the portionsRb, Rc, Rd, and Re near the four corners of the substrate G. In thiscase, the supply amount of the resist solution 9 from the first nozzle251a is greater than the supply amount of the resist solutions 9 fromthe second to fifth nozzles 251b to 251e. Once supply of the resistsolution 9 to the substrate W is completed, the rectangular block 250 ismoved back to a home position shown in FIG. 25B from a use positionshown in FIG. 25A. Further, the peripheral edge resist remover mechanism23A is moved form a home position to a use position.

As shown in FIG. 24C, the lids 231 and 241 are attached to the cups 55Aand 80A, and the spin chuck 38 and the rotation cup 55A aresynchronously rotated at a rotation speed of 200 to 800 rpm. Further,the spin chuck 38 and the rotation cup 55A are synchronously rotated ata rotation speed of 500 to 1500 rpm. In this manner, as shown in FIG.26, a resist solution 9 is diffused from the portion Ra at the rotationcenter portion to the concentric circle region 88 surrounded by atwo-dot chain line, and also, resist solutions 9 are respectivelydiffused from the portions Rb, Rc, Rd, and Re in the vicinity of thefour corners the four corner to regions 89 each surrounded by a two-dotchain line. Further, the substrate G is rotated at a rotation speed of1000 to 3000 rpm. As a result, the resist solution 9 completely spreadsover the entire surface of the substrate G, and the film thickness ofthe resist film is adjusted uniformly. Thus, the resist solution 9 issupplied over the entire surface of the substrate G. and a resist film9a having a uniform thickness is formed.

In the resist application step described above, an air introduced froman air hole 234a is exhausted from an exhaust hole 234b, and as aresult, mist of scattered resist solution 9 is exhausted together with aair, from the rotation cup 55A. In addition, an air which has enteredinto the drain cup 80A from an air hole 244a is exhausted from anexhaust hole 245b by rotation of the rotation cup 55A. In this manner,mist of the resist solution 9 which has flowed into the drain cup 80Aduring rotation of the rotation cup 55A is exhausted from the exhausthole 245b.

As shown in FIGS. 24D and 25B, the lids 231 and 241 are detached fromthe cups 55A and 80A, the peripheral edge resist remover mechanism 23Ais positioned with respect to the long edges of the substrate G and asolvent 8 is sprayed to the peripheral portion of the substrate G toremove an unnecessary resist film 9b from the substrate G. Further, asshown in FIG. 25C, the orientation of the substrate G is changed by 90°,and the peripheral edge resist remover mechanism 23A is positioned withrespect to the short edges of the substrate G. The solvent 8 is alsosprayed to the peripheral edge portion of the substrate G to remove anunnecessary resist film 9b from the substrate G.

In the apparatus according to the embodiment described above, the wasteamount of the resist solution 9 is reduced so that the total consumptionamount of the resist solution 9 can be greatly reduced. Specifically, bysupplying resist solutions 9 to the portions Rb to Re at the fourcorners of the substrate G, insufficient supply of the resist solutionfrom the portion Ra at the rotation center portion can be supplemented.Therefore, in case of attaining a throughput substantially equal to thatof a conventional apparatus, the consumption amount of a resist solutioncan be saved more than in a conventional apparatus.

Further, in the apparatus according to the above embodiment, sinceresist application processing and peripheral edge resist removalprocessing are carried out on one same spin chuck, the apparatus itselfis downsized more than in a conventional apparatus.

The position or timing of the supply of the resist solution is notlimited to the above-described examples, but it is possible that theresist solution is supplied at a plurality of sections of the substrateat the same time. In this manner, the through-put can be improved.

Also, as shown in FIG. 27A, while supplying the resist solution 9 to theportion Rf at the rotation center portion of the substrate G, the resistsolution 9 may be supplied to two portions Rg and Rh positionedpoint-symmetrically around the portion Rf as a center.

In addition, as shown in FIG. 27B, while supplying the resist solution 9to the portion Ri at the rotation center portion of the substrate G, theresist solution 9 may be supplied to four portions Rj, Rk, Rl, and Rmpositioned point-symmetrically around the portion Rf as a center, on thediagonal lines L1 and L2.

Also, as shown in FIG. 27C, while supplying the resist solution 9 to theportion Ri at the rotation center portion of the substrate G, the resistsolution 9 may be supplied to band-like portions Ro, Rp, Rq, and Rrextending radially around the portion Rn as a center. Note that thenumber of band-like portions is not limited to four but may be one, two,three, five, or six. In the example shown in FIG. 27C, it is possible touse slit nozzles having discharge ports respectively having shapescorresponding to the portions Ro, Rp, Rq, and Rr. Also, the resistsolution 9 may be supplied to the band-like portions Ro, Rp, Rq, and Rrby moving each of four nozzles (not shown) from the rotation centerportion toward the peripheral portions.

Further, as shown in FIG. 27D, while supplying the resist solution 9 tothe portion Rs at the rotation center portion of the substrate G, theresist solution 9 may be supplied to a circular portion Rt on theconcentric circle around the portion Rs as a center. The resist solution9 at the circular portion Rt supplements the resist solution diffusedfrom the portion Rs, and as a result, the resist solution 9 spreads tothe four corner regions of the substrate G. In the example shown in FIG.27D, it is possible to use a slit nozzle having a discharge port havinga shape corresponding to the circular portion Rt (ref. FIG. 16).

Further, when the amount of the resist solution supplied to each ofthese sections is adjusted independently depending upon the site, theamount of the resist consumed can be even more reduced. In the case of asupply system having a plurality of supply openings, such as the nozzleassembly 205, a mechanism (not shown) for adjusting the amount of theresist solution supplied, may be provided for each supply opening.

Next, another embodiment will be explained with reference to FIGS. 28 to30.

In the apparatus according to the present embodiment, a process liquidsupply section (or nozzle assembly) 270 and a peripheral edge resistremover section (or edge remover) 271 are moved by a common drivemechanism 273. The edge remover 271 is equipped at an edge of the nozzleassembly 270 having a rectangular shape. A movable arm 272 is equippedat another edge of the nozzle assembly 270. The drive mechanism 273comprises the movable arm 272 for supporting the nozzle assembly 270 andthe edge remover 271, a ball screw mechanism 274 for guiding and movingthe movable arm 272 in the Y-axis direction, and an elevation mechanism(not shown) for elevating up the movable arm 272. The nozzle assembly270 and the edge remover 271 are on standby at a home position outsidethe cup 55A when not used, and are moved above the cup 55A when used.

The edge remover 271 is slightly longer than the long edges of thesubstrate G, and a number of discharge ports 271a communicating with theheader are opened at a lower portion the edge remover 271. The header ofthe edge remover 271 is supplied with a solvent 8 from a solvent supplysource, and the inside of the header is always filled with the solvent8.

The nozzle assembly 270 is substantially the same as the nozzle assembly250 described before. However, a solvent nozzle 252 and an edge remover271 of the nozzle assembly 270 use, in common, a part of a supplycircuit. Specifically, a tube 252a communicates with the solvent nozzle252 and also communicates with a header (not shown) of the edge remover271 through a branch (not shown).

Operation of the above apparatus will be explained below.

In a resist application step, the nozzle assembly 270 is positionedabove a substrate G, a resist solution 9 is supplied to appropriateportions of the substrate G, and the substrate G is spun. Meanwhile, ina peripheral edge resist remove step, the lids 231 and 241 are detachedfrom the cups 55A and 80A, the edge remover 271 is positioned along anedge of the substrate G, and a solvent 8 is sprayed toward the edgeportion of the substrate G. As shown in FIG. 30, a solvent 8 is sprayedfrom the edge remover 271 to the peripheral edge portion of thesubstrate G by a water head pressure (or a pressure of a pressure gas).By thus spraying the solvent 8, the resist film 9a is dissolved anddissolved materials thereof flow into the drain cup provided below.After the resist film 9a is thus removed from the long edges of thesubstrate G, the orientation of the substrate G is changed by 90°, andfurther, the resist film 9a is removed from the short edges of thesubstrate G by the edge remover 271.

In the embodiment described above, since the drive mechanism 273 is usedin common by the nozzle assembly 270 and the edge remover 271, theapparatus itself can further be downsized. In addition, since the edgeremover 271 is equipped in the nozzle assembly 270, a part of a supplycircuit of the solvent 8 can be used in common, and the supply circuitof the solvent can be shortened as a whole.

In the next, another embodiment will be explained with reference toFIGS. 31 to 33.

In the apparatus according to the embodiment, an edge remover 208(including 208a to 208d) is equipped on the lid 231 of the rotation cup55A. As shown in FIG. 32, the edge remover 208 comprises a pair of slitportions 208a and 208c which are shorter than long edges of arectification plate 232, and a pair of slit portions 208b and 208d whichare shorter than short edges of the rectification plate 232. Inner endsides of the slit portions 208a to 208d are seated on the peripheraledges of a holding base 281, and outer end sides thereof are seated onthe lid 231 of the rotation cup 55A.

As shown in FIG. 33, each of the slit portions 208a to 208d comprises aplate-like base 280 provided above an edge portion of the rectificationplate 232. End plates 280a are provided at both ends of the base 280. Aslit-like discharge portion 282 for spraying a solvent to an end edge ofthe upper surface of the rectification plate 232 projects inwards,penetrating through the base 280, and extends in the lengthwisedirection of the base 280. A head 283 for storing a solvent 8 isprovided above the base 280. The solvent discharge port may be a narrowhole in place of a slit.

Solvent supply paths 284a to 284d are formed inside the holding base 281to supply the solvent 8 to the heads 283, respectively. The solventsupply paths 284a to 284d communicate with a solvent supply tube 285.The other end of the solvent supply tube 285 is connected to a solventsupply tube 252a. An air hole not shown corresponding to an air hole234a is formed in the holding base 281.

Next, operation of the apparatus described above will be explainedbelow.

The film remover section 208 functions as a part of the lid 231, and therotation cup 55A and the lid 231 rotate integrally. When removing aresist film 9a from an edge portion of a substrate G, the inside of therotation cup 55A is kept air-tight and a solvent 8 is sprayed from thesolvent discharge portions 282 to the vicinities of the end edges of thesurface of the rectification plate 232 substantially over the entireperiphery of the rectification plate.

In this manner, as shown in FIG. 33, the direction of the flow of thesolvent 8 is changed by the end edges of the rectification plate 232 sothat the solvent flows inwards from the lower portion of therectification plate 232. Thus, the solvent 8 is sprayed to the edgeportion of the substrate G. The resist film 9a is dissolved by thespraying force of the solvent 8, and dissolved materials thereof aredrained to the drain cup below.

In the embodiment described above, since a movement mechanism is used incommon by the edge remover 208 and the lid 231, the apparatus itself canbe downsized. In addition, after application processing of the resistsolution 9 is carried out, processing of removing the resist film can besequentially be carried out with a substrate G enclosed in the rotationcup 3. Therefore, it is possible to shorten the time required forprosecuting the processing from the application processing of the resistsolution 9 to the remove processing of the resist film.

In addition, since the lid 231 and the rotation cup 55A are rotatedsynchronously, positions of the slit portions 208a to 208d cannot beshifted with respect to the rectification plate 232 during processing ifonly the slit portions 208a to 208d are positioned so as to correspondto the edges of the rectification plate 232 (or the substrate G). If thepositions are previously adjusted, it is advantageous that removeprocessing of the resist film 9a can be performed successively withoutpositioning after carrying out application processing of the resistsolution 9.

Next, a third embodiment of the present invention will be explained withreference to FIGS. 34 to 43.

As shown in FIG. 34, an application unit 22B comprises a spin chuck 38,a rotation cup 55, a lid 71, a robot arm 75, a drain cup 80, a solventsupply nozzle 370, and a resist solution supply nozzle 380.

Each of supply paths of the nozzles 370 and 380 is provided with atemperature control mechanism 391, and there is provided a temperaturecontrol mechanism 91 for circulating and supplying a solvent 8 and aresist solution 9 at a target temperature (e.g., 23° C.).

The solvent supply nozzle 370a has a slit-like liquid discharge port 370as shown in FIG. 35. The solvent supply nozzle 370 communicates with asolvent tank 97 through a circuit having an opening/closing valve 96. Asshown in FIG. 34, a pressure of N₂ gas is supplied into the solvent tank97 thereby to supply the solvent 8 to the nozzle 370 from the tank 97.

As shown in FIG. 36, the solvent supply nozzle 370 is equipped on a pairof support members 375 by a shaft 374, and the paired support members375 are provided so as to sandwich the rotation cup 55 therebetween. Apair of guide members for respectively guiding the support members 375are provided outside the rotation cup 55. A pair of pulleys 379 arerespectively provided outside the guide members 376, and belts 377 arewound around the pulleys 379. The support members 375 are attached tothe belts 377, and one of the pulleys 379 is installed on a drive shaftof a motor 378. Therefore, the pair of support members 375 are moved inthe Y-axis direction by rotation drive of the motor 378, respectivelyguided by the guide rails 376, and the solvent supply nozzle 370 ismoved accordingly. Further, the solvent supply nozzle 370 is movablebetween a discharge position at any position above a substrate G and aturnout position indicated by a two-dot chain line and situated apartfrom the substrate G. The length of the nozzle 370 is slightly largerthan the long edges of the substrate G.

As shown in FIG. 37, a receive member 395 can be attached to a lowerportion of the solvent supply nozzle 370. The receive member 395comprises a dish-like body 395a provided below the nozzle 370, a supportmember 396 extending upwards in the vertical direction from the body,and a drain port 398 provided in the body. Attachment and detachment ofthe receive member 395 with respect to the solvent supply nozzle 370 areperformed by a lock mechanism 392. The lock mechanism 392 includes alock member 394 and a support pin 397. The lock member 394 is providedon a shaft 393 projecting form both side surfaces in the lengthwisedirection of the solvent nozzle 370 such that the lock member 394 can berotated between a lock position and a release position. The support pin397 is provided to be capable of projecting into the support member 396of the receive member 395 and can be inserted into a hole of the lockmember 94. The receive member is locked by rotating the lock member 394to the lock position thereby making the support pin 397 project and beinserted into the hole of the lock member 394, so that the receivemember 395 is rendered movable integrally with the solvent supply nozzle370. In case of releasing the lock, the support pin 397 is moved backand the lock member 394 is rotated to the release position. Note thatthe drain port 398 is connected with a tube 399 and a solvent pooled inthe receive member 395 is drained to a collection portion not shownthrough the tube 399.

The resist solution supply nozzle 380 communicates with the resistsolution tank 256 through a tube 381. The tube 381 is provided with asuck-back valve V1, an air operation valve V2, a scrub remover mechanism257, a filter 211, and a bellows pump 258. By the bellows pump 258, itis possible to realize control which achieves a smaller supply amountthan in a conventional apparatus.

As shown in FIG. 38, the resist supply nozzle 380 is supported on asupport member 403 and can be moved between a home position and a useposition by a movement mechanism 400. The movement mechanism 400includes a drive mechanism (not shown), a rotation shaft 402 fortransmitting rotation torque from the drive mechanism, and a movablemember 401 equipped at an upper portion of the rotation shaft 402 androtated together with the rotation shaft 402. A support member 403 isfixed to the movable member 401.

Next, explanation will be made of a case in which a resist film isformed on a substrate G and a resist film is removed from the peripheraledge portion of the substrate G, with reference to FIG. 39.

At first, the lid 71 is detached from the rotation cup 55 to release theupper opening 55c. A substrate G is conveyed into the apparatus 22B bythe second main arm mechanism 14B (in a step S31). The substrate G istransferred from the holder of the main arm mechanism 14B to the spinchuck 38 and is suctioned and held by vacuum by the spin chuck (in astep S32).

The nozzle 370 is moved from a home position to a use position (in astep S33). With rotation of the substrate G stopped, for example, 26.7cc of mixture of PGME and PGMEA is supplied as a solvent 8 of a processliquid, onto the surface of the substrate from the liquid discharge port370a while scanning the substrate from an end portion to the other endportion, and pre-wet processing is thus carried out (in a step S34). Dueto this processing, a resist solution 9 to be thereafter supplied can bediffused with ease, so that the use amount of the resist solution 9 canbe reduced. After supply of the solvent, the substrate G may be rotatedat a low speed of about 100 to 600 rpm. Also, in this state, the lockmechanism 392 is released and the receive member 395 is positioned at aturnout position.

Next, the nozzle 370 is moved back to the turnout position (in a stepS35). The support member 403 is moved in the Y-axis direction by themovement mechanism 400, and the nozzle 380 is moved to a use positionfrom a home position (in a step S36). Further, while rotating the spinchuck 38 and the rotation cup 55, for example, at a speed of 600 to 1000rpm as a first rotation speed, 10 cc of resist solution 9 is dischargefrom the nozzle 380 to the center of a solvent film 8a formed on thesubstrate (in a step S37). In this state, supply of the resist solutionis carried out before an applied solvent 8 is dried. Thus, the resistsolution can be diffused over the entire surface of the substrate byrotating the substrate G at a relatively low speed, so that the useamount of the resist solution 9 can be reduced much more.

After discharging the resist solution, rotation of the spin chuck 38 andthe rotation cup 55 is stopped and the nozzle 380 is moved back to thehome position (in a step S38). Further, the lid 71 is mounted on therotation cup 55 by the robot arm 75, and the opening portion 55c isclosed by the lid 71 (in a step S39).

In this state, the spin chuck 38 and the rotation cup 55 are rotated forfifteen seconds, for example, at 1350 rpm as a much higher secondrotation speed than the first rotation speed, to adjust the filmthickness of the resist film 9a (in a step S40). By thus rotating thesubstrate G in a closed condition, a much more uniform film can beobtained.

After the step is completed, rotation of the spin chuck 38 and therotation cup 55 is stopped (in a step S41), and the spin chuck 38 iselevated up (in a step S42). Further, the nozzle 370 is moved again tothe discharge position above the substrate (in a step S43). In thiscase, the receive member 395 is locked by the lock mechanism 392, andthe nozzle 370 is moved together with the receive member 395 so that thedischarge port 370a comes to a position corresponding to the peripheraledge portion of the substrate G, as shown in FIG. 40. The substrate G isclamped between the nozzle 370 and the receive member 395. Further, asolvent 8 is supplied to the peripheral edge portion of the substrate Gfrom the liquid discharge port 370a of the nozzle 370, and a resist film9a is removed from the peripheral edge portion, thus collecting thesolvent and the dissolved resist from the receive member 395 (in a stepS44).

Upon completion of cleaning of the peripheral edge portion of an edge ofthe substrate G, the spin chuck 38 is rotated by 90°, and removal of theperipheral resist is similarly performed on a next edge of the substrateG. This process is repeated four times so that the resist film 9a isremoved from the peripheral edge portions of all the edges of thesubstrate G.

After a series of processing for application processing is completed asdescribed above, the lid 71 is moved to a standby position by the robotarm 75. The substrate G is conveyed out of the unit 22B and is conveyedto a heating unit 26 in a next step (in a step S45).

Thus, in the present embodiment, the amount of the resist solutionconsumed can be reduced by pre-wetting, and cleaning of peripheral edgeportions of the substrate G can be realized by the nozzle 370 used forpre-wetting the solvent 8. Therefore, any additional equipment is notnecessary to clean materials sticking to the peripheral edge portion ofthe substrate, and it is possible to avoid enlargement of the size ofequipment. In addition, since a nozzle which moves along a peripheraledge of a substrate is not required, the problem of the positionaccuracy of the nozzle is overcome.

With respect to a rectangular LCD substrate G, a nozzle 370 having aslit-like liquid discharge port 370a is used and peripheral edgeportions at the edges of the substrate G is cleaned while rotating thesubstrate G. Therefore, an edge of a substrate G can be cleaned bydischarging a solvent for one time, and the peripheral edge portions ofthe substrate can be cleaned by only the rotation of the substrate Gwithout moving the solvent supply nozzle 70, so that a very highefficiency is achieved. Further, when cleaning is performed, the spinchuck 38 is elevated up thereby to perform cleaning processing with thesubstrate G raised and without having a mutual interference between thenozzle 370 and the cup 55. It is therefore possible to facilitatecleaning of the peripheral edge portions of the substrate. Furthermore,since the receive member 395 is positioned below the substrate G whencleaning a peripheral edge portion of a substrate, the solvent used forcleaning the substrate can be rapidly collected so that harmfulinfluences from the solvent can be restricted.

In addition, as shown in FIG. 41, it is possible to use a solvent supplynozzle 470 having a plurality of independent liquid flow lines 471 and aplurality of slit-like liquid discharge ports 470a corresponding to theplurality of liquid flow lines 471. In this case, the flow rate of eachof the liquid flow lines 471 is controlled independently so that thecleaning ability can be increased with respect to the peripheral edgeportions of the substrate.

As shown in FIG. 42, it is possible to use a nozzle 570 having a longbody 572 and a plurality of discharge ports 571 provided at a lowerportion of the body, so that a solvent 8 is discharge like a shower.

Further, the resist supply nozzle is not limited to the embodimentsdescribed above but may be a nozzle which vaporizes and supplies aresist solution or a slit nozzle. If a slit nozzle is used, it ispossible to use a solvent supply nozzle 670 with opening 672 integratedwith a resist supply nozzle 680 with opening 682, as shown in FIG. 43.

In the embodiments described above, a processing vessel and a substrateare rotated together. However, only the substrate may be rotated.Although the above embodiments have been explained to a case where aresist solution is used as a process liquid, the present invention isapplicable to another kind of process liquid.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

What is claimed is:
 1. A film forming method comprising the steps of:(a)holding a rectangular substrate by a spin chuck provided in a cup; (b)positioning a solvent supply nozzle above the rectangular substrate andsupplying a solvent to the rectangular substrate, said solvent supplynozzle having a liquid discharge port which has a length at leastcorresponding to that of a peripheral portion of the rectangularsubstrate; (c) positioning a process liquid supply nozzle above therectangular substrate and supplying a process liquid to a portion at arotation center portion of the rectangular substrate, thereby to form afilm; (d) rotating the rectangular substrate in the cup to adjust a filmthickness of the film; and (e) thereafter positioning the solvent supplynozzle above one peripheral portion of the rectangular substrate andsupplying the solvent to said one peripheral portion of the rectangularsubstrate, whereby the film is removed from said one peripheral portionof the rectangular substrate, the substrate being subsequently rotatedby the spin chuck to position the solvent supply nozzle to anotherperipheral portion of the rectangular substrate, whereby the film isremoved from said another peripheral portion of the rectangularsubstrate.
 2. A method according to claim 1, wherein in the step (d), alid is provided to cover the cup and the substrate is rotated with aperipheral atmosphere of the substrate kept air-tight.
 3. A methodaccording to claim 1, wherein in the step (c), the process liquid issupplied to the portion at the rotation center portion of the substratewhile rotating the substrate at a first rotation speed, and in the step(d), the substrate is rotated at a second rotation speed higher than thefirst rotation speed.
 4. A method according to claim 1, wherein in thestep (c), the process liquid is supplied to the portion at the rotationcenter portion of the substrate while rotating the substrate at a firstrotation speed, and in the step (d), a lid is provided to cover the cupand the substrate is rotated at a second rotation speed higher than thefirst rotation speed with a peripheral atmosphere of the substrate keptair-tight.
 5. A method according to claim 1, wherein in the step (e),the substrate is elevated up by the spin chuck, so that the substrate ispositioned to be higher in the step (e) than in the step (d).
 6. Amethod according to claim 1, further comprising, in the step (b), movingsaid solvent supply nozzle to a turnout position after the solvent issupplied to the rectangular substrate.
 7. A method according to claim 1,further comprising, in the step (c), moving said process liquid supplynozzle to a home position after the process liquid is supplied to theportion at the rotation center portion of the rectangular substrate. 8.A method according to claim 3, wherein the first rotation speed is inthe range of about 600-1000 revolutions per minute (rpm) and the secondrotation speed is about 1350 rpm.
 9. A method according to claim 4,wherein the first rotation speed is in the range of about 600-1000revolutions per minute (rpm) and the second rotation speed is about 1350rpm.